Phosphine-mediated partial reduction of alkynes to form both (E)- and (Z)- alkenes

Electronic Supplementary Material (ESI) for Organic & Biomolecular Chemistry. This journal is The Royal Society of Chemistry 2018 Supporting Information Phosphine-mediated partial reduction of alkynes to form both (E)- and (Z)- alkenes Brett M. Pierce, Brittany F. Simpson, Kane H. Ferguson, and Rachel E. Whittaker * Department of Chemistry, Murray State University, Murray, KY, 42071 Email: rwhittaker1@murraystate.edu Contents 1.) General.. S2 2.) Experimental Procedures and Characterization Data... S3 3.) 1 H-NMR and 13 C-NMR Spectra for Alkene Products........ S17 4.) References.S35 S1

1. General Experimental Methods Air and moisture-sensitive reactions were carried out in flame-dried glassware under nitrogen. All other reactions were setup in 8 ml oven-dried glass vials under an ambient atmosphere. Unless otherwise indicated, reagents and materials were obtained from commercial suppliers and used without further purification. Analytical TLC was performed with 0.25 mm silica gel F plates with a 254 nm indicator. Purification of products was achieved by column chromatography on Sorbtech silica gel (40-60 µm), with the indicated solvents. NMR spectra were measured on a Joel 400 Hz (ECS-400) nuclear magnetic resonance spectrometer. For CDCl 3 solutions the chemical shifts are reported as parts per million (ppm) referenced to residual protium or carbon of the solvents; CDCl 3 δ 1 H (7.26 ppm) and CDCl 3 δ 13 C (77.0 ppm). Coupling constants are reported in Hertz (Hz). Characterization data for 1 H-NMR spectra are reported as followed: chemical shift (ppm, s = singlet, d = doublet, dd = doublet of doublets, t = triplet, td = triplet of doublets, q = quartet, m = multiplet), and integration. Infrared spectra were recorded on a Perkin Elmer FTIR Spectrum II spectrometer, and are reported in wavenumber (cm -1 ) and relative intensity (br = broad, vw = very weak, w = weak, s = strong, vs = very strong, sh = shoulder). Abbreviations: PPh 3 = triphenylphosphine THF = tetrahydrofuran DCM = dichloromethane EtOAc = ethyl acetate n-buli = n-butyllithium TEA = triethylamine DMF = dimethylformamide Et 2O = diethyl ether S2

2. Experimental Procedures and Characterization Data General Procedure 1: Preparation of Ynoate Substrates (1a and 1f): Procedure adapted from the literature. 1 To a flame-dried Schlenk flask, a solution of the corresponding terminal alkyne (1.0 equiv.) and dry THF (0.25 M) was cooled to 0 C under nitrogen. n- BuLi (1.1 equiv.) was added dropwise, and the reaction solution was stirred for 1 hr at this temperature. Ethyl chloroformate (1.5 equiv.) was added dropwise, and the reaction was allowed to warm to rt. The reaction solution was quenched with DI water after 3 hr, extracted with EtOAc, and dried over MgSO 4 to afford the crude product. The solvent was removed under reduced pressure, and the crude product was purified via column chromatography on silica gel with hexanes/etoac and concentrated to afford the ynoate compound. Ynoate substrates 1a and 1f are known compounds from the literature. 2,3 Ethyl 3-phenylpropiolate (1a) 2 : Product isolated as a yellow oil (624.2 mg, 3.58 mmol, 73%). 1 H- NMR (400MHz, CDCl 3) δ 7.58-7.56 (m, 2H), 7.45-7.41 (m, 1H), 7.37-7.33 (m, 2H), 4.31-4.26 (q, J = 8 Hz, 2H), 1.36-1.32 (t, J = 8 Hz, 3H). IR (cm -1 ): 2235.0 (sh), 2209.5, 1703.6 (vs), 1490.2 (w), 1444.6 (w), 1390.2 (vw), 1366.7, 1282.5 (vs), 1187.9 (vs), 1171.5 (sh), 1114.4 (sh), 1019.6. Ethyl 4,4-dimethylpent-2-ynoate (1f) 3 : Product isolated as a colorless oil (119.7 mg, 0.776 mmol, 74%). 1 H-NMR (400MHz, CDCl 3) δ 4.24-4.18 (q, J = 8 Hz, 2H), 1.32-1.28 (t, J = 8 Hz, 3H), 1.28 (s, 9H). IR (cm -1 ): 2973.1, 2930.1 (sh), 2871.4, 2222.1, 1709.6 (vs), 1459.9 (w), 1365.8, 1272.1 (s), 1220.2 (vs), 1095.1 (vw), 1034.5 (s). S3

General Procedure 2: Preparation of Ynoate Substrates (1b-1e): Procedure adapted from the literature. 4 To a flame-dried Schlenk flask, a solution of the corresponding 2,2-dibromoethenyl compound (1.0 equiv.) and dry THF (0.25 M) was cooled to 0 C under nitrogen. n-buli (2.0 equiv.) was added dropwise, and the reaction solution was stirred for 1 hr at this temperature. Ethyl chloroformate (1.5 equiv.) was added dropwise, and the reaction was allowed to warm to rt. The reaction solution was quenched with DI water after 1 hr, extracted with EtOAc, washed with brine, and dried over MgSO 4 to afford the crude product. The solvents were removed under reduced pressure, and the crude product was purified via column chromatography on silica gel with hexanes/etoac and concentrated to afford the ynoate compound. Ynoate substrates 1b-1e are compounds known to literature. 4-6 Ethyl 3-(4-methoxyphenyl)-prop-2-ynoate (1b) 4 : Product isolated as a yellow-white solid (116.2 mg, 0.569 mmol, 68%). 1 H-NMR (400MHz, CDCl 3) δ 7.55-7.53 (d, J = 8 Hz, 2H), 6.89-6.87 (d, J = 8 Hz, 2H), 4.31-4.26 (q, J = 8 Hz, 2H), 3.83 (s, 3H), 1.37-1.33 (t, J = 8 Hz, 3H). IR (cm -1 ): 2986.5 (vw), 2934.3 (sh), 2203.1, 1700.3 (s), 1603.0, 1598.0, 1497.2 (w), 1444.8 (sh), 1370.2 (w), 1284.0 (s), 1250.2 (s), 1191.5 (s), 1158.2 (vs), 1022.0 (s). Ethyl 3-(4-chlorophenyl)-prop-2-ynoate (1c) 4 : Product isolated as a red solid (520.0 mg, 2.887 mmol, 88%). 1 H-NMR (400MHz, CDCl 3) δ 7.53-7.51 (d, J = 8 Hz, 2H), 7.37-7.35 (d, J = 8 Hz, 2H), 4.33-4.27 S4

(q, J = 8 Hz, 2H), 1.37-1.34 (t, J = 8 Hz, 3H). IR (cm -1 ): 2243.7 (sh), 2210.4, 1698.8 (s), 1592.8 (w), 1481.7, 1286.2 (vs), 1187.6 (vs), 1085.6, 1011.9. (4-nitrophenyl)-Propynoic acid ethyl ester (1d) 5 : Product isolated as an orange solid (20.8 mg, 0.0949 mmol, 19%). 1 H-NMR (400MHz, CDCl 3) δ 8.26-8.24 (d, J = 8 Hz, 2H), 7.76-7.74 (d, J = 8 Hz, 2H), 4.36-4.30 (q, J = 8 Hz, 2H), 1.39-1.36 (t, J = 8 Hz, 3H). IR (cm -1 ): 2965.7 (sh), 2924.5, 2236.2 (w), 1701.1 (vs), 1600.3 (w), 1516.2 (vs), 1345.8 (s), 1290.1 (s), 1192.3 (vs), 1110.2 (sh), 1019.9. O-Tolyl-propynoic acid ethyl ester (1e) 6 : Product isolated as an amber oil (235.0 mg, 1.249 mmol, 83%). 1 H-NMR (400MHz, CDCl 3) δ 7.55-7.53 (d, J = 8 Hz, 1H), 7.35-7.31 (t, J = 8 Hz, 1H), 7.27-7.23 (t, J = 8 Hz, 1H), 7.16-7.20 (t, J = 8 Hz, 1H), 4.33-4.28 (q, J = 8 Hz, 2H), 2.49 (s, 3H), 1.38-1.34 (t, J = 8 Hz, 3H). IR (cm -1 ): 2982.8 (vw), 2938.0 (sh), 2209.3 (sh), 2206.0, 1704.8 (vs), 1785.8 (w), 1366.7, 1294.0 (sh), 1185.7 (vs), 1023.4. General Procedure 3: Preparation of Ynone Substrates (4a-4e): Procedure adapted from the literature. 7 To a flame-dried Schlenk flask, a solution of phenylacetylene (1.0 equiv.) and dry THF (0.25 M) was cooled to 0 C under nitrogen. n-buli (1.1 equiv.) was added dropwise, and the reaction solution was stirred for 1 hr at this temperature. The corresponding aldehyde (1.5 equiv.) was added dropwise, and the reaction was allowed to warm to rt. The S5

reaction solution was quenched with DI water after 4 hr, extracted with EtOAc, and dried over MgSO 4. The solvents were removed under reduced pressure to give the crude alcohol product to which DCM (0.25 M) and MnO 2 (10 equiv) were added and the solution was stirred at rt and in the dark for two hr. The reaction solution was filtered over celite, solvents were removed, and the crude product was purified via column chromatography on silica gel with hexanes/etoac and concentrated to afford the ynone compound. The ynone substrates 4a-4e are compounds known to literature. 8-11 1,3-Diphenylprop-2-yn-1-one (4a) 8 : Product isolated as a white solid (220.2 mg, 1.068 mmol, 86%). 1 H-NMR (400MHz, CDCl 3) δ 8.25-8.22 (m, 2H), 7.71-7.69 (m, 2H), 7.66-7.62 (t, J = 8 Hz, 1H), 7.55-7.52 (m, 2H), 7.51-7.48 (t, J = 8 Hz, 1H), 7.45-7.41 (t, J = 8 Hz, 2H). IR (cm -1 ): 2195.6 (s), 1630.4 (vs), 1600.3, 1488.0, 1450.7, 1313.6, 1286.9 (s), 1206.5 (s), 1168.9, 1010.4 (s). 1-(4-methoxyphenyl)-3-phenylprop-2-yn-1-one (4b) 9 : Product isolated as a yellow-white solid (519.3 mg, 2.198 mmol, 88%). 1 H-NMR (400MHz, CDCl 3) δ 8.22-8.18 (m, 2H), 7.69-7.67 (m, 2H), 7.50-7.46 (m, 1H), 7.44-7.40 (m, 2H), 7.01-6.98 (m, 2H), 3.91 (s, 3H). IR (cm -1 ): 2194.9 (s), 1626.8 (s), 1594.9 (vs), 1569.8 (sh), 1510.5, 1420.7 (w), 1256.6 (s), 1155.2, 1027.9, 1009.2 (sh). 1-(4-bromophenyl)-3-phenylprop-2-yne-1-one (4c) 10 : Product isolated as a white solid (125.8 mg, 0.441 mmol, 88%). 1 H-NMR (400MHz, CDCl 3) δ 8.10-8.07 (m, 2H), 7.70-7.65 (m, 4H), 7.53-7.49 (m, 1H), 7.46-7.42 (t, J = 8 Hz, 2H). IR (cm -1 ): 2197.7 (vs), 1652.1, 1585.6 (w), 1394.5 (vw), 1298.5, 1206.7, 1169.7, 1067.7 (w). S6

4-Phenyl-3-butyn-2-one (4d) 8 : Product isolated as a clear, yellow oil (608.4 mg, 4.22 mmol, 86%). 1 H- NMR (400MHz, CDCl 3) δ 7.58-7.57 (d, J = 4 Hz, 2H), 7.47-7.43 (m, 1H), 7.40-7.36 (m, 2H), 2.45 (s, 3H). IR (cm -1 ): 2200.0 (s), 1668.4 (vs), 1489.4 (w), 1447.0 (w), 1424.5 (w), 1357.7, 1278.2, 1154.6 (s), 1020.5 (vw). 1-Cyclohexyl-3-phenylprop-2-yn-1-one (4e) 11 : Product isolated as a colorless oil (571.0 mg, 2.690 mmol, 94%). 1 H-NMR (400MHz, CDCl 3) δ 7.59-7.57 (m, 2H), 7.47-7.43 (m, 1H), 7.40-7.36 (m, 2H), 2.09-2.03 (m, 2H), 1.84-1.79 (m, 2H), 1.55-1.45 (m, 2H), 1.39-1.32 (m, 2H), 1.30-1.21 (m, 2H). IR (cm - 1 ): 2929.0, 2854.1 (sh), 2197.7 (s), 1661.2 (vs), 1491.8 (w), 1446.4, 1262.5, 1142.0 (w), 1091.1 (sh), 1070.2. Preparation of 1-Morpholino-3-phenylprop-2-yn-1-one (4f) 12 : Procedure adapted from the literature. 12 To a flame-dried Schlenk flask with a solution of 3- phenylpropiolic acid (1.0 equiv.) and DCM (0.27 M), TEA (2.0 equiv.) and oxalyl chloride (1.3 equiv.) was added dropwise at 0 C under nitrogen. Morpholine (1.1 equiv.) was added, and the reaction proceeded at rt for 5 hr. The reaction solution was extracted with EtOAc, washed with brine and dried over Na 2SO 4 to afford the crude product. The solvents were removed under reduced pressure, and the crude product was purified via column chromatography on silica gel with hexanes/etoac and concentrated to afford 4f (247.1 mg, 1.148 mmol, 84%) as a yellow solid. 1 H-NMR (400MHz, CDCl 3) δ 7.56-7.54 (d, J = 8 Hz, 2H), 7.45-7.42 (m, 1H), 7.39-7.35 (t, J = 8 Hz, 2H), 3.90 (s, 2H), 3.78-3.72 (m, 6H). IR (cm -1 ): 2920.8 (sh), 2864.7 (w), 2217.5, 1617.4 (vs), 1495.5, 1428.3 (s), 1278.8, 1213.1, 1110.0 (s), 1042.9. S7

Preparation of 3-Phenylpropiolaldehyde (4g) 13 : Procedure adapted from the literature. 13 To a flame-dried Schlenk flask, a solution of phenylacetylene (1.0 equiv.) and dry THF (0.25 M) was cooled to 0 C under nitrogen. n-buli (1.1 equiv.) was added dropwise, and the reaction solution was stirred for 1 hr. DMF (2 equiv.) was added followed by a temperature elevation to rt, and the solution stirred for 1 hr. The reaction solution was quenched with DI water, extracted with EtOAc, and dried over MgSO 4. The solvents were removed under reduced pressure, and the crude product was purified via column chromatography on silica gel with hexanes/etoac and concentrated to afford 4g (94.4 mg, 0.7253 mmol, 36%) as a yellow oil. 1 H-NMR (400MHz, CDCl 3) δ 9.43 (s, 1H), 7.62-7.60 (m, 2H), 7.52-7.48 (m, 1H), 7.43-7.39 (m, 2H). IR (cm -1 ): 2953.6 (sh), 2924.0 (vs), 2853.9 (s), 1730.6 (w), 1461.8, 756.9 (w), 693.5 (w). Synthesis of (E)-Alkene Products (2a-2e, 5a-5g): To an oven-dried 8 ml reaction vial was added PPh 3 (1.5 equiv.), benzoic acid (1.5 equiv.), the corresponding substrate (1.0 equiv, 0.10 mmol), DI water (25 equiv.), and dry THF (0.1 M). The solution was heated to 65 C and stirred for 24 hr. The solvents were removed under reduced pressure, toluene was added, and the solution dried over MgSO 4. The toluene was removed under reduced pressure, and cold Et 2O was added and filtered over silica. Et 2O was removed under reduced pressure, and the crude residue was purified via column chromatography on silica gel with hexanes/et 2O (100:1 to 20:1) to afford the alkene product. All (E)-alkene products 2a-2e and 5a-5g are compounds known to literature. 14-26 S8

The E/Z selectivity was 86:14 from 1 H-NMR spectroscopic analysis of the crude residue. Trans-Ethyl cinnamate (2a) 14 : Product isolated as a colorless oil (14.2 mg, 0.0806 mmol, 81%). 1 H- NMR (400MHz, CDCl 3) δ 7.71-7.67 (d, J = 16 Hz, 1H), 7.54-7.52 (m, 2H), 7.39-7.38 (m, 3H), 6.46-6.42 (d, J = 16 Hz, 1H), 4.30-4.24 (q, J = 8 Hz, 2H), 1.36-1.33 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 167.2, 144.7, 134.6, 130.4, 129.0, 128.2, 118.4, 60.7, 14.5. IR (cm -1 ): 2925.0, 2861.0 (sh), 1712.4 (vs), 1638.3, 1450.1 (w), 1368.4 (w), 1309.7, 1268.2 (w), 1201.4 (sh), 1171.4 (vs), 1039.2, 980.0. Cis-Ethyl cinnamate (3a): Product isolated as a colorless oil (1.8 mg, 0.0102 mmol, 10%). Total yield (16.0 mg, 0.0908 mmol, 91%). The E/Z selectivity was 92:8 from 1 H-NMR spectroscopic analysis of the crude residue. Ethyl (E)-3-(4-methoxyphenyl) acrylate (2b) 15 : Product isolated as a white solid (16.7 mg, 0.0810 mmol, 84%). 1 H-NMR (400MHz, CDCl 3) δ 7.66-7.62 (d, J = 16 Hz, 1H), 7.49-7.47 (d, J = 8 Hz, 2H), 6.91-6.89 (d, J = 8 Hz, 2H), 6.33-6.29 (d, J = 16 Hz, 1H), 4.28-4.23 (q, J = 8 Hz, 2H), 3.84 (s, 3H), 1.35-1.31 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 167.5, 161.5, 144.4, 129.8, 127.3, 115.9, 114.4, 60.5, 55.5, 14.5. IR (cm -1 ): 1706.8, 1633.7 (w), 1604.0, 1512.2, 1304.3 (sh), 1288.5 (w), 1252.1 (s), 1167.4 (vs), 1031.6. MP: 45.2-46.6 C. The E/Z selectivity was 75:25 from 1 H-NMR spectroscopic analysis of the crude residue. Ethyl (E)-3-(4-chlorophenyl) acrylate (2c) 16 : Product isolated as a colorless oil (15.7 mg, 0.0745 mmol, 68%). 1 H-NMR (400MHz, CDCl 3) δ 7.65-7.61 (d, J = 16 Hz, 1H), 7.46-7.43 (m, 2H), 7.37-7.34 (m, 2H), 6.42-6.38 (d, J = 16 Hz, 1H), 4.29-4.24 (q, J = 8 Hz, 2H), 1.35-1.31 (t, J = 8 Hz, 3H). 13 C-NMR S9

(400MHz, CDCl 3) δ 166.8, 143.2, 136.2, 133.0, 129.3, 129.2, 118.9, 60.7, 14.4. IR (cm -1 ): 1710.4 (s), 1638.2, 1491.1, 1309.1 (s), 1268.5, 1201.1 (sh), 1168.1 (vs), 1088.2, 1035.6, 980.4. Ethyl (Z)-3-(4-chlorophenyl) acrylate (3c): Product isolated as a colorless oil (3.4 mg, 0.0161 mmol, 15%). Total yield (19.1 mg, 0.0907 mmol, 83%). The E/Z selectivity was 76:24 from 1 H-NMR spectroscopic analysis of the crude residue (The (Z)-isomer was not isolated). Total yield (17.4 mg, 0.0787 mmol, 90%). Ethyl (E)-3-(4-nitrophenyl) acrylate (2d) 17 : Product isolated as a tan solid. 1 H-NMR (400MHz, CDCl 3) δ 8.26-8.24 (d, J = 8 Hz, 2H), 7.73-7.66 (m, 3H), 6.58-6.54 (d, J = 16 Hz, 1H), 4.32-4.27 (q, J = 8 Hz, 2H), 1.37-1.33 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 166.1, 148.5, 141.7, 140.7, 128.7, 124.3, 122.7, 61.1, 14.4. IR (cm -1 ): 1710.2 (vs), 1645.2 (w), 1596.7 (w), 1518.0, 1343.9 (vs), 1310.4 (sh), 1192.4, 1117.3 (w), 1031.8 (w), 978.7 (w). MP: 130.6-133.3 C. The E/Z selectivity was 42:58 from 1 H-NMR spectroscopic analysis of the crude residue (The (Z)-isomer was not isolated). Total yield (18.0 mg, 0.0946 mmol, 68%). Ethyl (E)-3-(o-tolyl) acrylate (2e) 18 : Product isolated as a yellow oil. 1 H-NMR (400MHz, CDCl 3) δ 8.00-7.96 (d, J = 16 Hz, 1H), 7.56-7.54 (d, J = 8 Hz, 1H), 7.30-7.28 (d, J = 8 Hz, 1H), 7.23-7.19 (t, J = 8 Hz, 2H), 6.38-6.34 (d, J = 16 Hz, 1H), 4.30-4.22 (q, J = 8 Hz, 2H), 2.44 (s, 3H), 1.36-1.33 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 168.6, 142.4, 130.9, 130.1, 126.5, 126.4, 119.4, 60.7, 19.9, 14.5. IR (cm -1 ): 2924.3 (vs), 2859.6, 1717.3 (s), 1639.0 (w), 1467.2 (w), 1318.0, 1269.4, 1179.8 (s), 1041.7 (w), 985.7 (vw). S10

The E/Z selectivity of the reaction was >99:1 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-Chalcone (5a) 19 : Product isolated as a white solid (17.1 mg, 0.0821 mmol, 90%). 1 H-NMR (400MHz, CDCl 3) δ 7.71-7.67 (d, J = 16 Hz, 1H), 7.54-7.52 (m, 2H), 7.39-7.38 (m, 3H), 6.46-6.42 (d, J = 16 Hz, 1H), 4.30-4.24 (q, J = 8 Hz, 2H), 1.36-1.33 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 167.2, 144.7, 134.6, 130.4, 129.0, 128.2, 118.4, 60.7, 14.5. IR (cm -1 ): 2925.0, 2861.0 (sh), 1712.4 (vs), 1638.3, 1450.1 (w), 1368.4 (w), 1309.7, 1268.2 (w), 1201.4 (sh), 1171.4 (vs), 1039.2, 980.0. MP: 51.6-54.4 C. The E/Z selectivity of the reaction was >99:1 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-1-(4-methoxyphenyl)-3-phenylprop-2-en-1-one (5b) 20 : Product isolated as a white solid (15.6 mg, 0.0655 mmol, 68%). 1 H-NMR (400MHz, CDCl 3) δ 8.06-8.04 (d, J = 8 Hz, 2H), 7.83-7.79 (d, J = 16 Hz, 1H), 7.65-7.64 (m, 2H), 7.57-7.53 (d, J = 16 Hz, 1H), 7.43-7.41 (m, 3H), 7.00-6.98 (d, J = 8 Hz, 2H), 3.90 (s, 3H). 13 C-NMR (400MHz, CDCl 3) δ 188.9, 163.6, 144.1, 135.2, 131.2, 131.0, 130.5, 129.1, 128.5, 122.0, 114.0, 55.7. IR (cm -1 ): 2917.0 (w), 1656.4, 1597.6 (vs), 1570.8 (sh), 1255.6, 1220.6, 1181.0 (s), 1013.9, 971.7 (s). MP: 98.9-100.6 C The E/Z selectivity of the reaction was >99:1 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-1-(4-bromophenyl)-3-phenylprop-2-en-1-one (5c) 21 : Product isolated as a white solid (27.3 mg, 0.0951 mmol, 83%). 1 H-NMR (400MHz, CDCl 3) δ 7.90-7.88 (d, J = 8 Hz, 2H), 7.84-7.80 (d, J = 16 Hz, 1H), 7.66-7.64 (m, 4H), 7.50-7.46 (d, J = 16 Hz, 1H), 7.44-7.42 (m, 3H). 13 C-NMR (400MHz, CDCl 3) δ 189.6, 145.6, 137.1, 134.8, 132.1, 130.9, 130.2, 129.2, 128.7, 128.1, 121.6. IR (cm -1 ): 2924.8, 1659.1 (vs), 1603.4 (vs), 1583.1 (sh), 1450.7 (w), 1336.1, 1217.8, 1069.4, 1008.5, 982.2. MP: 97.2-98.9 C S11

The E/Z selectivity of the reaction was >99:1 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-4-phenylbut-3-en-one (5d) 22 : Product isolated as a yellow oil (9.8 mg, 0.0670 mmol, 71%). 1 H- NMR (400MHz, CDCl 3) δ 7.56-7.50 (m, 3H), 7.41-7.40 (m, 3H), 6.74-6.70 (d, J = 16 Hz, 1H), 2.39 (s, 3H). 13 C-NMR (400MHz, CDCl 3) δ 198.6, 143.6, 130.7, 129.1, 128.4, 127.3, 27.7. IR (cm -1 ): 2855.0 (vw), 2810.0 (sh), 1690.2 (sh), 1668.1 (vs), 1601.0, 1450.5 (w), 1358.8 (w), 1256.8 (s), 1204.5 (w), 1178.4 (w). The E/Z selectivity was 98:2 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-1-cyclohexyl-3-phenylprop-2-en-1-one (5e) 23 : Product isolated as a white solid (18.1 mg, 0.845 mmol, 91%). 1 H-NMR (400MHz, CDCl 3) δ 7.61-7.55 (m, 3H), 7.40-7.38 (m, 3H), 6.84-6.80 (d, J = 16 Hz, 1H), 2.70-2.63 (m, 1H), 1.92-1.88 (m, 2H), 1.86-1.81 (m, 2H), 1.73-1.69 (m, 1H), 1.48-1.23 (m, 5H). 13 C-NMR (400MHz, CDCl 3) δ 203.4, 142.4, 134.9, 130.4, 129.0, 128.4, 124.9, 49.6, 28.9, 26.1, 25.9. IR (cm -1 ): 2928.7 (s), 1680.4 (s), 1604.8 (s), 1446.6, 1338.4, 1319.7, 1200.0, 1065.8. MP: 54.8-56.2 C. The E/Z selectivity was 95:5 from 1 H-NMR spectroscopic analysis of the crude residue. (E)-1-morpholino-3-phenylprop-2-en-1-one (5f) 24 : Product isolated as a white solid (10.0 mg, 0.0460 mmol, 53%). 1 H-NMR (400MHz, CDCl 3) δ 7.72-7.68 (d, J = 16 Hz, 1H), 7.54-7.51 (m, 2H), 7.38-7.36 (m, 3H), 6.86-6.82 (d, J = 16 Hz, 1H), 3.73 (s, 8H). 13 C-NMR (400MHz, CDCl 3) δ 165.7, 143.4, 135.2, 129.9, 128.9, 127.9, 116.6, 67.0. IR (cm -1 ): 2923.8, 2853.8, 1649.1 (vs), 1603.7, 1459.2 (sh), 1431.4, 1228.3, 1115.2, 1044.0 (w), 977.9 (w). MP: 60.1-63.5 C. S12

The E/Z selectivity was >99:1 from 1 H-NMR spectroscopic analysis of the crude residue. trans-cinnamaldehyde (5g) 25 : Product isolated as a yellow oil (9.6 mg, 0.0726 mmol, 87%). 1 H-NMR (400MHz, CDCl 3) δ 9.73-9.71 (d, J = 8 Hz, 1H), 7.59-7.57 (m, 2H), 7.51-7.47 (d, J = 16 Hz, 1H), 7.47-7.44 (m, 3H), 6.76-6.70 (dd, J = 8 Hz, 16Hz, 1H). 13 C-NMR (400MHz, CDCl 3) δ 193.9, 152.9, 134.1, 131.4, 129.2, 128.7, 128.6. IR (cm -1 ): 2924.8 (w), 2853.3 (w), 1676.7 (vs), 1625.8, 1450.4 (vw), 1254.3 (vw), 1123.5, 973.0. The E/Z selectivity was 97:3 from 1 H-NMR spectroscopic analysis of the crude residue. The reaction was run using D 2O instead of H 2O. (E)-2-Propenoic-2,3-d 2 acid, 3-phenyl-ethyl ester (2a-D): Product isolated as a colorless oil (24.2 mg, 0.1358 mmol, 66%). 1 H-NMR (400MHz, CDCl 3) δ 7.54-7.52 (m, 2H), 7.39-7.38 (m, 3H), 4.30-4.24 (q, J = 8 Hz, 2H), 1.36-1.32 (7, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 167.1, 144.3 (t), 134.5, 130.4, 129.0, 128.2, 118.0 (t), 60.6, 14.5. IR (cm -1 ): 2921.3 (w), 1706.8 (vs), 1608.0, 1447.9 (w), 1366.1 (w), 1266.4 (s), 1200.4 (vs), 1084.2 (vw), 1049.2. (Z)-2-Propenoic-2,3-d 2 acid, 3-phenyl-ethyl ester (3a-D): Product isolated as a colorless oil (0.6 mg, 0.0034 mmol, 2%). Total yield (24.8mg, 0.1391 mmol, 68%). Synthesis of (Z)-Alkene Products (3a-3e): To an oven-dried 8 ml reaction vial was added PPh 3 (1.5 equiv.), the corresponding substrate (1.0 equiv, 0.10 mmol), DI water (40 equiv.), and dry THF (0.1 M). The solution was heated to 65 C and stirred for 24 hr. The solvents were removed under reduced pressure, toluene was added, and the solution S13

dried over MgSO 4. The toluene was removed under reduced pressure, and cold Et 2O was added and filtered over silica. Et 2O was removed under reduced pressure, and the crude residue was purified via column chromatography on silica gel with hexanes/et 2O (100:1 to 10:1) to afford the alkene product. All cis-alkene products 3a-3e are compounds known to literature. 26-29 The E/Z selectivity was 15:85 from 1 H-NMR spectroscopic analysis of the crude residue. Cis-Ethyl cinnamate (3a) 26 : Product isolated as a colorless oil (10.1 mg, 0.0573 mmol, 56%). 1 H-NMR (400MHz, CDCl 3) δ 7.59-7.57 (m, 2H), 7.37-7.32 (m, 3H), 6.97-6.94 (d, J = 12 Hz, 1H), 5.97-5.94 (d, J = 12 Hz, 1H), 4.20-4.15 (q, J = 8 Hz, 2H), 1.26-1.23 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 166.3, 143.1, 135.0, 129.8, 129.1, 128.1, 120.0, 60.4, 14.2. IR (cm -1 ): 2924.1, 2853.7 (sh), 1720.1 (s), 1629.5, 1452.2 (w), 1262.3 (w), 1161.6 (vs), 1028.5, 830.3 (w). Trans-Ethyl cinnamate (2a): Product isolated as a colorless oil (2.1 mg, 0.0119 mmol, 12%). Total yield (12.2 mg, 0.0692 mmol, 68%). The E/Z selectivity was 22:78 from 1 H-NMR spectroscopic analysis of the crude residue. Ethyl (Z)-3-(4-methoxyphenyl) acrylate (3b) 26 : The (Z)-isomer was inseparable from the remaining starting material through column chromatography. 1 H-NMR (400MHz, CDCl 3) δ 7.70-7.68 (d, J = 8 Hz, 2H), 6.87-6.83 (m, 3H), 5.84-5.81 (d, J = 12 Hz, 1H), 4.22-4.16 (q, J = 8 Hz, 2H), 3.83 (s, 3H), 1.30-1.26 (t, J = 8 Hz, 3H). S14

The E/Z selectivity was 12:88 from 1 H-NMR spectroscopic analysis of the crude residue. Ethyl (Z)-3-(4-chlorophenyl) acrylate (3c) 27 : Product isolated as a colorless oil (21.6 mg, 0.1026 mmol, 68%). 1 H-NMR (400MHz, CDCl 3) δ 7.56-7.54 (d, J = 8 Hz, 2H), 7.33-7.31 (d, J = 8 Hz, 2H), 6.90-6.87 (d, J = 12 Hz, 1H), 5.97-5.94 (d, J = 12 Hz, 1H), 4.20-4.15 (q, J = 8Hz, 2H), 1.28-1.24 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 166.0, 142.0, 135.0, 133.3, 131.3, 128.3, 120.5, 60.5, 14.2. IR (cm -1 ): 1718.0 (s), 1630.8, 1591.5 (vw), 1491.2, 1442.1 (vw), 1397.9 (w), 1175.2 (vs), 1092.8, 1029.4, 1016.1, 849.1. Ethyl (E)-3-(4-chlorophenyl) acrylate (2c): Product isolated as a colorless oil (3.6 mg, 0.0171 mmol, 10%). Total yield (25.2 mg, 0.1196 mmol, 80%). The E/Z selectivity was 28:72 from 1 H-NMR spectroscopic analysis of the crude residue (The (E)-isomer was not isolated). Total yield (9.8 mg, 0.0443 mmol, 87%). Ethyl (Z)-3-(4-nitrophenyl) acrylate (S33) 28 : Product isolated as yellow solid. 1 H-NMR (400MHz, CDCl 3) δ 8.22-8.20 (d, J = 8 Hz, 2H), 7.68-7.66 (d, J = 8 Hz, 2H), 7.03-6.99 (d, J = 12 Hz, 1H), 6.14-6.11 (d, J = 12 Hz, 1H), 4.20-4.15 (q, J = 8 Hz, 2H), 1.26-1.22 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 165.4, 147.6, 141.6, 140.7, 130.3, 123.4, 123.3, 60.8, 14.1. IR (cm -1 ): 2930.3, 1718.1 (vs), 1596.9, 1521.1 (vs), 1466.7 (vw), 1345.2 (s), 1299.4 (w), 1218.1 (s), 1058.3 (w), 857.3 (w). MP: 85.6-87.9 C. S15

The E/Z selectivity was 2:98 from 1 H-NMR spectroscopic analysis of the crude residue. Ethyl (Z)-3-(o-tolyl) acrylate (3e) 29 : Product isolated as a tan oil (15.4 mg, 0.0809 mmol, 69%). 1 H- NMR (400MHz, CDCl 3) δ 7.22-7.15 (m, 4H), 7.14-7.11 (d, J = 12 Hz, 1H), 6.04-6.01 (d, J = 12 Hz, 1H), 4.11-4.06 (q, J = 8 Hz, 2H), 1.11-1.08 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 159.2, 143.1, 129.7, 128.9, 128.5, 125.3, 121.2, 60.3, 20.0, 14.1. IR (cm -1 ): 2962.0 (sh), 2924.0 (vs), 2851.6, 1735.5, 1465.1, 1381.3 (w), 1267.0 (w), 1175.6, 1118.5 (w), 1023.3 (w), 977.6. The E/Z selectivity was 17:83 from 1 H-NMR spectroscopic analysis of the crude residue. The reaction was run using D 2O instead of H 2O. (Z)-2-Propenoic-2,3-d 2 acid, 3-phenyl-ethyl ester (3a-D): Product isolated as a clear oil (25.2 mg, 0.1414 mmol, 74%). 1 H-NMR (400MHz, CDCl 3) δ 7.61-7.59 (m, 2H), 7.38-7.32 (m, 3H), 4.21-4.15 (q, J = 8 Hz, 2H), 1.27-1.23 (t, J = 8 Hz, 3H). 13 C-NMR (400MHz, CDCl 3) δ 166.4, 142.8 (t), 134.5, 129.9, 129.1, 128.1, 119.5 (t), 60.4, 14.2. IR (cm -1 ): 2923.4 2853.3 (sh), 1738.0 (vs), 1606.0 (w), 1461.3 (s), 1377.5, 1267.7 (s), 1171.8, 1057.5. (E)-2-Propenoic-2,3-d 2 acid, 3-phenyl-ethyl ester (2a-D): Product isolated as a colorless oil (5.3 mg, 0.0297 mmol, 16%). Total yield (30.5 mg, 0.1711 mmol, 90%). 3. 1 H-NMR and 13 C-NMR Spectra for Alkene Products S16

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